Effects of cis-2-butene-1,4-diol additive and pulse current imposition on production of Ni nanocrystalline coatings

Abstract

Nickel nanocrystalline electrodeposits were produced from a Watts type bath with the addition of cis-2-butene-1,4-diol and simultaneous application of either direct or pulse current conditions. The surface morphology, the preferred orientation, grain size and microhardness of Ni deposits were determined as functions of the concentration of the additive in bath, the type of imposed current and the frequency of imposed current pulses. The combined imposition of predefined pulse current conditions (pulse frequency) and specific additive concentration in the bath leads to specific textural modifications ([211] and [100] preferred crystal orientations) accompanied by considerable nanosized grain refinement of the coatings. The overall experimental data indicate that the production of hard and bright nanostructured deposits could be obtained under pulse current regime and reduced amounts of cis-2-butene-1,4-diol compared to direct plating.

Keywords:

• Nickel electrodeposition
• Organic additive
• Pulse current
• Preferred orientation
• Nanocrystalline
• Microhardness

This paper is based on a presentation given at the 5th European Pulse Plating Seminar, Vienna, Austria, 9th March 2012. The authors would like to thank Dr. P. Schinas for accomplishing SEM images. The assistance given in preparation of coatings by Mrs. A. Gialamopoulou is also appreciated.